Low-profile high-gain omnidirectional V2X antenna applied to automobile skylight glass

Abstract

The utility model discloses a low-profile high-gain omnidirectional V2X antenna applied to automobile skylight glass. The low-profile high-gain omnidirectional V2X antenna comprises a first dielectric substrate, a first radiation patch, a second radiation patch, a radio frequency connector and a glass substrate, the first radiation patch is printed on the upper surface of the first dielectric substrate, and eight M-shaped slots which are arranged in a central symmetry manner are formed in the first radiation patch; the periphery of the first radiation patch is sleeved with at least three coaxial annular coupling patches at intervals. The glass substrate is bonded and fixed on the upper surface of the first dielectric substrate; the second radiation patch is printed on the lower surface of the first dielectric substrate and is connected with the first radiation patch through a metal pin, and the second radiation patch comprises a regular octagonal metal patch and eight tree-shaped metal branches; each vertex angle of the regular octagonal ring-shaped metal patch of the second radiation patch is correspondingly provided with a tree-shaped metal stub; the radio frequency connector is fixed at the center of the first radiation patch. The antenna is small in size, low in profile, high in gain and good in omnidirectivity.

Description

Technical Field

[0001] The utility model relates to the technical field of vehicle-mounted antennas, in particular to a low-profile high-gain omnidirectional V2X antenna applied to an automobile sunroof glass. Background Art

[0002] With the rapid development of technologies such as artificial intelligence, 5G communication, and big data, intelligent connected vehicles are becoming the focus of the global automotive industry. The realization of vehicle networking requires the completion of vehicle-to-everything (V2X). Currently, the dedicated communication frequency band for vehicle networking (intelligent connected vehicles) issued in China is 5905 MHz - 5925 MHz. V2X includes V2V, V2I, V2P, and V2N, which respectively represent vehicle-to-vehicle communication, vehicle-to-infrastructure communication, vehicle-to-pedestrian communication, and vehicle-to-network communication with vehicle-mounted base stations. V2X communication needs to take into account low elevation angle communication scenarios such as vehicle-to-vehicle, vehicle-to-person, vehicle-to-roadside base station, and vehicle-to-roadside infrastructure. Especially when there are blind spots in vehicle-mounted radar detection in scenarios such as highway turning or right-angle turning with obstacles blocking, to ensure the safety and risk avoidance needs of autonomous vehicles, it is necessary to rely on the high-gain omnidirectional radiation in the horizontal direction of the V2X antenna to ensure sufficient communication range and distance. Therefore, for vehicle-mounted V2X antennas, ensuring the radiation gain in the horizontal direction is a major feature that differentiates V2X antenna design from traditional vehicle-mounted vertical dipole antennas. The maximum radiation direction of a vertical dipole antenna located on a non-ideal conductor plane tilts towards the zenith. This electromagnetic characteristic is widely used in vehicle-mounted wireless mobile communication, and at the same time, it poses a major challenge to the low elevation angle high-gain omnidirectional radiation of V2X antennas at a limited height. In recent years, many new methods for the design of vehicle-mounted V2X have been proposed internationally, but there is no unified standard for their design forms.

[0003] The shark fin-type vehicle-mounted antenna is located on the top of the vehicle. Structurally, it is generally equipped with a plastic shell and a metal base, and the antenna inside is generally printed by PCB. In recent years, there have emerged vehicle-mounted shark fin 3D printing antennas [18 - 19] and shark fin cover inner wall laser engraving process antennas

[20] similar to mobile phone antennas. These two solutions are applicable to 3D forms that are difficult to achieve with planar PCBs. However, their costs are relatively high. Among them, the 3D printed metal shakes greatly with the vehicle's bumps, and the shark fin inner wall laser engraving antenna is relatively difficult to debug. Therefore, in shark fin antennas, the PCB vertical board-mounted antenna solution is widely adopted due to its advantages of low cost, easy installation, and easy debugging.

[0004] Most of the layouts of shark fin antennas are arranged in a "one" shape front and back. To make full use of the internal space of the shark fin antenna cover, traditional ceramic patch antennas or dipole antennas with a small height are usually placed at the lower front end of the shark fin, and antennas that require a larger space height such as quadrifilar helix antennas, LTE antennas, V2X antennas, digital TV broadcast antennas, and FM antennas can be arranged at the back end.

[0005] However, the existing V2X antennas require communication with devices such as vehicles and roadside base stations, and need low elevation angle communication. Currently, most manufacturers place the V2X antennas in the shark fin. Affected by the metal on the roof, the antenna pattern has an upward tilt, and it is impossible to achieve bottom elevation angle communication. When the V2X antenna is placed in the shark fin, affected by the antenna and components, the non-circularity in the horizontal direction of the antenna is poor, the gain is weak in some directions, and the signal is poor. It cannot meet the communication requirements of the vehicle with the roadbed equipment in all directions during actual use. When the V2X antenna is placed in the roof shark fin, it is close to antennas such as 4G, GNSS, and WIFI, and the isolation is poor. The devices will affect each other and cannot meet the stable use of the devices. Most of the antennas on the market are placed in the roof shark fin, and the presence of the shark fin reduces the overall coordination and aesthetics of the vehicle. Currently, most of the V2X antennas on the market are placed in the metal roof shark fin, resulting in disadvantages such as upward tilt of the V2X antenna pattern, poor horizontal gain, poor antenna circularity, and poor isolation and large interference with other antennas, and cannot meet the application requirements of low elevation angle, high gain, and high isolation of in-vehicle V2X antennas. Summary of the Invention

[0006] The purpose of the present utility model is to provide a low-profile, high-gain omnidirectional V2X antenna applied to automotive sunroof glass, covering 5900 - 5925 MHz. The antenna is small in size, low in profile, high in gain, and good in omnidirectionality, and is suitable for automotive equipment.

[0007] The technical solution adopted by the present utility model is as follows:

[0008] A low-profile, high-gain omnidirectional V2X antenna applied to automotive sunroof glass, which includes a first dielectric substrate, a first radiation patch, a second radiation patch, a radio frequency connector, and a glass substrate; the first radiation patch is printed on the upper surface of the first dielectric substrate, and the first radiation patch includes a regular octagon metal patch. There are 8 M-shaped slots opened inside the regular octagon metal patch of the first radiation patch, and the 8 M-shaped slots are symmetrically arranged around the center of the regular octagon metal patch of the first radiation patch; at least three coaxial ring-shaped coupling patches are sleeved at intervals on the outer periphery of the regular octagon metal patch of the first radiation patch; the glass substrate is adhesively fixed on the upper surface of the first dielectric substrate;

[0009] The second radiation patch is printed on the lower surface of the first dielectric substrate, and the second radiation patch includes a regular octagon metal patch and 8 tree-shaped metal branches; each vertex of the regular octagon ring-shaped metal patch of the second radiation patch is correspondingly provided with a tree-shaped metal branch, and the tree-shaped metal branch extends towards the corresponding side edge of the first dielectric substrate;

[0010] The first radiation patch and the second radiation patch are connected by metal pins, and one end of the radio frequency connector is detachably fixed at the center of the first radiation patch.

[0011] Furthermore, it comprises a second dielectric substrate, and the upper surface of the first dielectric substrate is bonded to the glass substrate via the second dielectric substrate.

[0012] Furthermore, more than three metal pins are distributed on the regular octagonal ring-shaped metal patch of the second radiation patch.

[0013] Furthermore, eight metal pins are centrally symmetrically arranged on the regular octagonal ring-shaped metal patch of the second radiation patch.

[0014] Furthermore, the annular coupling patches are all regular octagonal annular metal patches.

[0015] Furthermore, the regular octagonal metal patches of the first radiation patch and the second radiation patch are symmetrically arranged on the upper and lower surfaces of the first dielectric substrate.

[0016] Further, the M-shaped opening of the M-shaped slot is arranged away from the center of the regular octagon of the first radiation patch.

[0017] Furthermore, the tree-shaped metal branches are formed by using negative magnetic permeability metamaterial.

[0018] Furthermore, a rear feed line is welded to the other end of the RF connector.

[0019] Furthermore, the first dielectric substrate has an outer shape of a regular octagonal structure;

[0020] Furthermore, the first dielectric substrate and the second dielectric substrate have the same appearance.

[0021] Furthermore, the second dielectric substrate has an outer shape of a regular octagonal structure;

[0022] Further, the size of the first dielectric substrate is smaller than that of the second dielectric substrate, or the size of the first dielectric substrate and the second dielectric substrate are the same.

[0023] Furthermore, the shape of the glass substrate is a square, and the overall structure of the glass substrate is larger than the first dielectric substrate, that is, the glass substrate completely covers the first dielectric substrate.

[0024] This utility model adopts the above technical solution. In order to solve the shortcomings of the existing vehicle-mounted V2X antenna, it innovatively designs a low-profile PCB antenna and creatively installs the antenna at the bottom of the car glass sunroof, solving the mutual interference problem with 5G, GNSS and other antennas. The car antenna glass is combined with the antenna design, and the reflection effect of the large dielectric constant of the glass material on electromagnetic waves is used to enable the antenna to achieve horizontal omnidirectional high-gain radiation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods;

[0026] Figure 1 Schematic diagram of the structure of a low-profile, high-gain omnidirectional V2X antenna for automotive sunroof glass according to the present utility model;

[0027] Figure 2 Bottom view schematic diagram of a low-profile, high-gain omnidirectional V2X antenna for automotive sunroof glass according to the present utility model;

[0028] Figure 3 Schematic diagram of the upper surface structure of the first dielectric substrate according to the present utility model;

[0029] Figure 4 Schematic diagram of the reflection coefficient (S11 parameter) of a low-profile, high-gain omnidirectional V2X antenna for automotive sunroof glass according to the present utility model;

[0030] Figure 5 Schematic diagram of the 3D radiation pattern of the gain of a low-profile, high-gain omnidirectional V2X antenna for automotive sunroof glass according to the present invention at Freq = 5.92 GHz;

[0031] Figure 6 XOY pattern of a low-profile, high-gain omnidirectional V2X antenna for automotive sunroof glass according to the present invention at Freq = 5.92 GHz;

[0032] Figure 7 YOZ pattern of a low-profile, high-gain omnidirectional V2X antenna for automotive sunroof glass according to the present invention at Freq = 5.92 GHz;

[0033] Figure 8 XOZ pattern of a low-profile, high-gain omnidirectional V2X antenna for automotive sunroof glass according to the present invention at Freq = 5.92 GHz. Embodiment

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application.

[0035] As Figures 1 to 8As shown in one of the figures, the utility model discloses a low-profile high-gain omnidirectional V2X antenna applied to an automotive sunroof glass, which comprises a first dielectric substrate 1, a first radiation patch 2, a second radiation patch 3, a radio frequency connector 10 and a glass substrate 8; the first radiation patch 2 is printed on the upper surface of the first dielectric substrate 1, and the first radiation patch 2 comprises a regular octagon metal patch, and 8 M-shaped slots 11 are formed inside the regular octagon metal patch of the first radiation patch 2, and the 8 M-shaped slots 11 are arranged in central symmetry with respect to the center of the regular octagon metal patch of the first radiation patch 2; at least three concentric annular coupling patches are sleeved at intervals on the outer periphery of the regular octagon metal patch of the first radiation patch 2; the glass substrate 8 is adhesively fixed on the upper surface of the first dielectric substrate 1;

[0036] The second radiation patch 3 is printed on the lower surface of the first dielectric substrate 1, and the second radiation patch 3 comprises a regular octagon metal patch and 8 tree-shaped metal branches 12; each vertex angle of the regular octagon annular metal patch of the second radiation patch 3 is correspondingly provided with a tree-shaped metal branch 12, and the tree-shaped metal branch 12 extends towards the corresponding side edge of the first dielectric substrate 1;

[0037] The first radiation patch 2 and the second radiation patch 3 are connected by a metal pin 9, and one end of the radio frequency connector 10 is detachably fixed at the center of the first radiation patch 2.

[0038] Furthermore, it comprises a second dielectric substrate 7, and the upper surface of the first dielectric substrate 1 is adhesively fixed on the glass substrate 8 through the second dielectric substrate 7.

[0039] Furthermore, more than three metal pins 9 are distributed on the regular octagon annular metal patch of the second radiation patch 3.

[0040] Furthermore, 8 metal pins 9 are arranged in central symmetry on the regular octagon annular metal patch of the second radiation patch 3.

[0041] Furthermore, the annular coupling patches are all regular octagon annular metal patches. They are the regular octagon annular metal patches 4, 5 and 6 in sequence from the inside to the outside.

[0042] Furthermore, the regular octagon metal patches of the first radiation patch 2 and the second radiation patch 3 are symmetrically arranged on the upper and lower surfaces of the first dielectric substrate 1.

[0043] Furthermore, the opening of the M shape of the M-shaped slot 11 is arranged away from the center of the regular octagon of the first radiation patch 2.

[0044] Furthermore, the tree-shaped metal branch 12 is formed by using a negative magnetic permeability metamaterial.

[0045] Furthermore, a rear feed line is welded to the other end of the radio frequency connector 10.

[0046] Further, the outer shape of the first dielectric substrate 1 is a regular octagon structure;

[0047] Further, the outer shape of the second dielectric substrate 7 is a regular octagon structure; the first dielectric substrate 1 and the second dielectric substrate 7 are of the same size.

[0048] Further, the outer shapes of the first dielectric substrate 1 and the second dielectric substrate 7 are the same.

[0049] Further, the outer shape of the second dielectric substrate 7 is a regular octagon structure;

[0050] Further, the size of the first dielectric substrate 1 is smaller than that of the second dielectric substrate 7, or the first dielectric substrate 1 and the second dielectric substrate 7 are of the same size.

[0051] Further, the outer shape of the glass substrate 8 is a square. The overall structure of the glass substrate 8 is larger than that of the first dielectric substrate 1. That is, the glass substrate 8 completely covers the first dielectric substrate 1.

[0052] To meet the requirement of installing the antenna inside the automotive sunroof glass, the antenna needs to have a low height to meet the automotive installation requirements. To reduce the profile height of the antenna, a regular octagon patch can be loaded on the top of the monopole to shorten the vertical height of the antenna. A center-fed regular octagon symmetric patch is used to generate the TM02 mode to achieve an omnidirectional radiation pattern.

[0053] In the present utility model, 8 "M"-shaped slots are opened on the first radiation patch 2 to increase the current path of the metal patch, reduce the antenna size, increase the current path, increase the resonance points, and expand the antenna bandwidth; an annular coupling patch is sleeved around the first radiation patch 2, namely regular octagon annular metal patches 4, 5, and 6. The zero-order resonance is excited through the short-circuit vias and the coupled annular coupling patches to achieve a relatively wide bandwidth. The first radiation patch 2, the regular octagon annular metal patches 4, 5, and 6 all have omnidirectional radiation characteristics in the horizontal plane.

[0054] The glass substrate has the characteristic of a large dielectric constant. Placing the glass substrate above the antenna as a cover can suppress the upward tilt of the antenna pattern, significantly improve the radiation directivity of the antenna, and thus increase the antenna gain in the horizontal plane; the second radiation patch 3 is printed on the lower surface of the first dielectric substrate. The regular octagon metal radiation patch of the second radiation patch 3 generates currents in the opposite direction to the octagon metal patch of the first radiation patch 2 on the upper surface, generating opposite electromagnetic waves in the up-down direction of the first dielectric substrate 1 to cancel each other out, making the antenna mainly radiate horizontally.

[0055] On the bottom surface of the first dielectric substrate 1, at the vertices of the regular octagonal metal radiation patch of the second radiation patch 3, 8 tree-shaped metal stubs 12 of negative permeability metamaterial are loaded outward, which can enhance the gain of the omnidirectional antenna. When electromagnetic waves are vertically incident on the metamaterial of the tree-shaped metal stub 12, negative permeability can be obtained in the frequency band where electromagnetic waves cannot propagate, thereby improving the antenna horizontal plane gain.

[0056] The antenna of the present utility model is fed by a central probe symmetrically, ensuring that the currents in all directions are consistent, thereby ensuring the omnidirectionality of the radiation pattern. The size of the antenna of the present utility model is 35mm×35mm×2.0mm, which is lower than the profiles of existing antennas. As Figures 4 to 8 shown, the minimum value of the simulated reflection coefficient of the antenna of the present utility model at 5900 - 5925MHz is -32dB; the simulated gain value at 5900MHz is 4.2dB, meeting the high gain requirement; the horizontal plane non-circularity at 5900MHz is 0.7dB, meeting the low non-circularity requirement; the 3dB vertical beamwidth is 120°, meeting the wide beamwidth requirement.

[0057] The present utility model adopts the above technical solutions. Compared with the prior art, the present utility model has the following advantages: covering the 5900 - 5925MHz frequency band, the antenna has good port impedance and can achieve a wide impedance bandwidth. The antenna has characteristics such as high gain, small size, low profile, small upward tilt angle, and good horizontal plane non-circularity, which are suitable for applications in automotive equipment.

[0058] Obviously, the described embodiments are part of the embodiments of the present application, rather than all embodiments. Without conflict, the embodiments and features in the present application can be combined with each other. Usually, the components of the embodiments of the present application described and illustrated in the drawings here can be arranged and designed in various different configurations. Therefore, the detailed description of the embodiments of the present application is not intended to limit the scope of the present application claimed, but merely represents the selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

Claims

1. A low-profile high-gain omnidirectional V2X antenna applied to automotive sunroof glass, characterized in that: It includes a first dielectric substrate, a first radiation patch, a second radiation patch, a radio frequency connector and a glass substrate; the first radiation patch is printed on the upper surface of the first dielectric substrate, the first radiation patch includes a regular octagon metal patch, and 8 M-shaped slots are opened inside the regular octagon metal patch of the first radiation patch, and the 8 M-shaped slots are symmetrically arranged around the center of the regular octagon metal patch of the first radiation patch; at least three coaxial annular coupling patches are sleeved at intervals on the outer periphery of the regular octagon metal patch of the first radiation patch; the glass substrate is adhesively fixed on the upper surface of the first dielectric substrate; The second radiation patch is printed on the lower surface of the first dielectric substrate, and the second radiation patch includes a regular octagon metal patch and 8 tree-shaped metal branches; a tree-shaped metal branch is correspondingly arranged at each vertex angle of the regular octagon-shaped metal patch of the second radiation patch, and the tree-shaped metal branch extends towards the corresponding side edge of the first dielectric substrate; The first radiation patch and the second radiation patch are connected by metal pins, and one end of the radio frequency connector is detachably fixed at the center of the first radiation patch.

2. The low-profile high-gain omnidirectional V2X antenna applied to the automotive sunroof glass according to claim 1, wherein: It includes a second dielectric substrate, and the upper surface of the first dielectric substrate is adhesively bonded to the glass substrate through the second dielectric substrate.

3. The low-profile high-gain omnidirectional V2X antenna applied to the automotive sunroof glass according to claim 1, characterized in that: More than three metal pins are distributed on the regular octagon-shaped metal patch of the second radiation patch.

4. A low-profile high-gain omnidirectional V2X antenna applied to an automotive sunroof glass according to claim 1, characterized in that: 8 metal pins are symmetrically arranged around the center of the regular octagon-shaped metal patch of the second radiation patch.

5. The low-profile high-gain omnidirectional V2X antenna applied to the automotive sunroof glass according to claim 1, wherein: The annular coupling patches are all regular octagon-shaped annular metal patches.

6. The low-profile high-gain omnidirectional V2X antenna applied to the automotive sunroof glass according to claim 1, wherein: The regular octagon metal patches of the first radiation patch and the second radiation patch are symmetrically arranged on the upper and lower surfaces of the first dielectric substrate.

7. A low-profile high-gain omnidirectional V2X antenna for automotive sunroof glass according to claim 1, characterized in that: The opening of the M shape of the M-shaped slot is arranged away from the center of the regular octagon of the first radiation patch.

8. The low-profile high-gain omnidirectional V2X antenna applied to the automotive sunroof glass according to claim 1, wherein: The tree-shaped metal branch is formed by a negative magnetic permeability metamaterial.

9. The low-profile high-gain omnidirectional V2X antenna applied to the automotive sunroof glass according to claim 1, wherein: The outer shape of the first dielectric substrate is a regular octagon structure; the outer shape of the glass substrate is a square.

10. A low-profile high-gain omnidirectional V2X antenna applied to automotive sunroof glass according to claim 1, characterized in that: The overall structure of the glass substrate is larger than that of the first dielectric substrate, that is, the glass substrate completely covers the first dielectric substrate.

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